The cryopreservation of body fluids, such as, peripheral blood, bone marrow and umbilical cord blood, including hematopoetic stem cells and other cells contained therein, has assumed immense commercial significance as the development in human medicine has progressed. Umbilical cord blood and its preservation over a number of years, known as long-term preservation, are crucially significant in connection with possible later treatment of a child, youngster or adult with means based on the body's own substances, for example, in the situation of a transplant. However, this valuable blood is available only at the birth of the child. After the umbilical cord has been cut, it still contains blood that is no longer required for the child.
In the case in which long-term preservation is intended, this blood, often an amount of blood with a volume of about 50 to 100 ml, is collected and prepared for cryopreservation and subsequently frozen by known methods. The aforementioned small amounts of blood removed must expediently be frozen and stored in such a way that a number of samples can be examined and used independently and at different times from one another, possibly several years apart, by the latest methods then available. Without knowledge, today, of the methods that may be applied in the future, cryopreservation of all constituents of the body fluid removed is considered appropriate.
Currently, separate open systems are used commercially for the preparation and freezing of the body fluids (Macropharma, Fresenius, Baxter), and require processing under sterile benches (clean room classes A and B) in a hospital or laboratory. Usually several individual containers or bags are used, requiring the transfer of fluid contents into other bags during processing after the original collection bag is opened. For instance, the umbilical cord blood is collected by a system which often comprises one or more removal cannulas, one or two containers which contain citrate, and the actual blood collecting container. The aforementioned parts of the system are connected in a communicating manner to one another by flexible tubes. Such a system is known in the prior art, for example from U.S. Pat. No. 5,879,318. However, such systems require the use of expensive ultra-clean rooms and many clinical centers use their own, non-standardized procedures for the processing of biological fluids, tissue, bone marrow or stem cells prior to freezing and storage. Consequently, such procedures carry a high risk of contamination of the cryopreserved preparation, particularly stem cell contents.
Following the preparation of the blood, decanting then takes place from one system into another for the purpose of cryopreservation. Thus the body fluids are moved from a sterile container into a sterile freezing container, which often has to be performed under ultra-clean room conditions. Often high expenditures are required to meet the statutory predetermined ultra-clean room conditions with respect to human medicine, such as, the requirements according to GMP. These sterile conditions and requirements for collecting body fluids in sterile form and preparing them for cryopreservation usually cannot be provided in every delivery ward or medical facility.
Accordingly, until the present invention, the preparation for cryopreservation of umbilical cord blood always took place by the following steps: 1) removing the blood from the umbilical cord and introducing it into the transporting bag, 2) adding citrate or preservative, unless already provided in the bag, 3) closing the bag and transporting the filled bag at room temperature to an ultra-clean room (necessarily within about 24 to 48 hours), and 4) transferring the blood and added cryoprotectant from the transporting bag into a sterile freezing bag under ultra-clean room conditions. Moreover, current processes require at least two separate systems—one for collection of the body fluids, such as the umbilical cord blood, and one for freezing the collected fluids.
Consequently, a need has remained for an expandable system and method for the collection, processing and cryopreservation of biological fluids and cells contained therein, that meet the sterile requirements for human medicine under normal hygienic laboratory conditions, without the need for the use of an expensive ultra-clean room, and without a need for dual or multiple independent systems for each step.